2023

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Devising sustainable methods for recycling industrial polyurethane waste
(UMT, Lhr, 2023) SHAH NOOR ALI
Research is being conducted to recycle and transform polyurethane into a valuable matrix material, addressing a major environmental concern. Buffing dust, often a byproduct of leather finishing processes, was utilized to enhance certain properties. This research focused on buffing dust and polyurethane waste for use in the construction industry. In the process of fabricating thermal insulation panels, a mixture of fresh polyurethane, polystyrene, buffing dust, and alumina nanoparticles was used to produce the PUC sample. On the other hand, the WPUC sample was synthesized by using waste polyurethane, glass fiber, polystyrene, buffing dust, and alumina nanoparticles. The PUC sample showed water absorption of up to 38%, while the WPUC sample displayed up to 44.6%. The FTIR study indicated that the both samples show the distinctive vibration of the –OH group of the amino acid found in discarded leather. SEM analysis of both samples showed that the addition of glass fiber and buffing dust led to the formation of voids. EDX analysis revealed that the PUC composite sample consisted of 2.38% Oxygen and 48.53% Carbon, while the WPUC composite material contained 1.94% Oxygen and 46.18% Carbon. Thermogravimetric analysis revealed that the PUC and WPUC samples exhibited thermal stability till 280 °C and 350 °C respectively. This effort aligns with the Sustainable Development Goal (SDG) No. 11, which emphasizes the creation of sustainable cities and communities.
Construction of a well-defined S-scheme Ni cos@S-g-C3N4 Heterojunction for Visible Light Driven Photocatalysis and Antimicrobial Performance
(UMT, Lhr, 2023) SHAKEELA RAUF
Direct discharge of waste, including organic dyes from various industries into the water bodies contributes significantly to environmental contamination. A detail research on the photocatalytic materials is much needed that may successfully remove the harmful pollutants from water in order to make water free from such dangerous contaminants. In this respect, CoS based photocatalysts have drawn a lot of attention because of their good stability, excellent conductivity, and relatively small band gap. In the current project, CoS nanoparticles, a series of Ni doped CoS (Ni-CoS) nanoparticles with varying percentage of Ni, and a series of Ni-CoS nanoparticles were made composite with sulphur doped graphitic carbon nitride (Ni-CoS/SCN) with varying concentrations of SCN using an easy, efficient, and affordable co-precipitation technique; however, SCN was synthesized through a thermal degradation process using thiourea as a precursor. Evaluation of synthesized photocatalysts was carried out by cutting edge techniques i.e.; FTIR and XRD. Photocatalytic degradation behaviour of the as prepared photocatalysts was observed by UV-Visible spectrophotometer and the doping of Ni-metal was thought to have contributed to the high rate of degradation of methylene blue, which was used as a standard pollutant dye. The greatest outcomes for doped NPs were from 6% Ni-CoS NPs. while the best photocatalytic activity was achieved by 6Ni-CoS@50 SCN NCs. EIS spectra for CoS, 6% Ni-CoS and 6Ni CoS@50 SCN was observed and they were examined for their antimicrobial performance as well.
Synthesis of chromium doped zinc oxideRGO nanocomposite for electrochemical applications
(UMT, Lhr, 2023) FAIQA ARSHAD
Reduced graphene oxide has been incorporated into metal-doped nanoparticles of zinc oxide to further enhance the material's characteristics and produce an electro-active material for energy storage devices including power banks, batteries, and capacitors. Herein simple, Eco-friendly, or economical approach was used to produce nanomaterials, for electrochemical applications. Chemical co-precipitation was used for the production of nanoparticles of chromium-doped zinc oxide (Crx-doped ZnO x=2-10 at%). X-ray powder diffraction, Scanning Electron Microscopy, Energy-dispersive X-ray, Atomic Absorption Spectroscopy (AAS), (ICP-OES), (UV-Visible) were used for the analysis of structure, morphology, composition, electrical properties of synthesized nanoparticles. SEM analysis shows spherical morphology. The FT-IR peaks in the range of 598 cm-1, 924 cm-1, 1177 cm-1, and 3447 cm-1 that correlate to the presence of Metal oxygen bonding, Cr-O stretching vibrations, C-O peak, and hydrogen bonded groups. The hexagonal wurtzite structure was confirmed for pure and Cr-doped ZnO nanoparticles. Corresponding to crystal planes (100), (002), (101), (102), (110), (103), (200), (112) and (201) for pure ZnO matched with literature and (220), (311) and (400) for Cr doped ZnO. The band gap of Pure ZnO, GO, and chromium-doped ZnO was observed in the range of 3.725, 3.66, and 3.59 eV. The concentration of chromium doping percentage in Cr-ZnO was confirmed by AAS and Zinc concentration by using ICP-OES. Cyclic voltammetry and EIS in 3 molar Potassium hydroxide electrolyte were used to determine the electrochemical effects of the chromium-doped zinc oxide (Crx-doped ZnO x=2–10 at %) nanomaterials. The 8% Cr-doped ZnO doping sample exhibited a 390.80 Fg−1 specific capacitance at a scan rate of 60 mV/s, which is 40% higher than the specific capacitance of pure zinc oxide nanoparticles, which is 154 Fg−1. For composite material, the specific capacitance value was calculated by using a formula that was about 703Fg−1. The shape of CV curves is rectangular as Electrical double-layer capacitance exhibits, and GO presents a Quasi-rectangular shape at 100 scan rates, which suggests good capacitive properties These brilliant electrochemical properties of 8% chromium-doped zinc oxide at reduced graphene oxide (Crx-ZnO x=8 at%) nanocomposite have shown that it is a favorable material for supercapacitor applications.
Removal of commercial dyes from aqueous media by adsorption on biochar prepared from beans of cassia fistula
(UMT, Lhr, 2023) SYEDA MEHAK ZAHRA NAQVI
Commercial dyes used in textile industry for dying the fabric are usually toxic and damage aquatic life in water significantly. Untreated industrial effluents flushed out in water channels are considered a major source of water pollution. In this work three commercial dyes: Safranine, Crystal Violet and Orange-2 are removed from aqueous media by adsorbing them on biochar. The biochar used in this work was prepared from a locally grown decorative plant Cassia Fistula commonly known as Amaltas in local language. This plant has been abundantly found in all areas of Punjab (Pakistan). In spring yellow clusters of flowers can be easily seen showering on the branches of this plant. On the end of spring season, one to two feet long beans of dark brown colour containing seeds are found hanging along with the branches of the plant. To prepare the biochar the dried beans were collected from the plants available in the campus (Punjab University, Lahore). The seeds were removed by crushing the beans and the skull was dried and pyrolyzed in a furnace under control temperature and little presence of air. The black lumps of biochar obtained were ground and sieved. All the three dyes mentioned above were adsorbed on this mass by shaking in aqueous media and under different conditions of temperature, pH, adsorbent dose and shaking speed and time etc. It was observed that under optimum conditions each of the above mentioned dyes can be eliminated from 95% to 99% in aqueous media. This method of removing the toxic dyes by adsorbing on biochar prepared by the pyrolysis of an indigenous plant material was found a simple, fast and inexpensive.
Artificial neural network based study for photocatalytic degradation of dyes in the presence of 3d transition metal doped zno
(UMT, Lhr, 2023) FADIA KHALID
Extensive research has been carried out on the degradation of organic pollutants through photocatalysis due to the increasing demand for wastewater that is free from pollutants. The results obtained from different experimental runs in photocatalytic degradation can be utilized in data-centric machine learning modeling methods like artificial neural networks. The optimization of 3d transition metal dopants for enhancing the photocatalytic degradation of dyes represents a promising approach in the field of environmental remediation. This study aims to leverage the power of neural networks to optimize the impact of such dopants on the mechanism of photocatalytic degradation. The photocatalytic degradation process is described using both Artificial Neural Networks (ANN). These models incorporated six degradation variables, namely the concentration of composite, concentration of the dye, temperature, pH, irradiation time, and the light intensity or wavelength, as input variables. It uses the degradation percentage of the dye as their output variable. By training neural networks on a comprehensive dataset of experimental observations, the relationships between various process parameters, dopant types, and the efficiency of dye degradation will be modeled and analyzed. The maximum R2 for the outcomes of this research can significantly contribute to the development of more efficient photocatalytic systems for dye removal, ultimately leading to improved environmental sustainability
Anti-diabetic activity of metal oxide nanoparticles on alloxan induced diabetic mice
(UMT, Lhr, 2023) GOHER AYUB
Diabetes is a metabolic disorder considered either due to the resistance of insulin or lack of insulin production and hyperglycemic effects. Metallic nanoparticles have been reported as therapeutic agent against many metabolic diseases. Our study was designed to analyze the anti-diabetic activity of synthesized metal oxide nanoparticles; Titanium oxide (TiO2), and Cobalt oxide (Co3O4) for drug delivery. The synthesis, crystallinity and purity of nanoparticles were confirmed by UV-Vis Spectroscopy, SEM, XRD, and EDX. Diabetes was induced by using alloxan dose in all mice except healthy mice group. The mice with a weight of 35±15 g were selected and grouped: Positive control group, negative control group, treatment group 1, treatment group 2 and standard treatment group. Positive group was healthy group; no treatment was given. Negative group was given alloxan dose continuously, third diabetic group was treated with titanium oxide nanoparticles, and forth group was treated with cobalt oxide nanoparticles while fifth group was treated with standard dose (Glucophage). The diabetic mice were compared with the treated and healthy group and the efficiency of the treatment was observed. The histopathology of liver and spleen showed better results as compared to the diabetic liver and diabetic mice. The Liver functioning test (LFTs) of diabetic and treated and non-diabetic mice was compared which showed that the lower level of Serum Glutamic Pyruvic Transaminase (S.P.G.T), Alkaline Phosphatase (ALP) and Aspartate Aminotransferase (AST) is a sign of efficient treatment against diabetes. The genes Glucokinase (GK), Insulin Resistance (IR) and Proteinase Kinase (AKT) and Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were targeted against the liver (diabetic, non-diabetic, treated) and gene expression was analyzed using Real-time PCR. The result showed the up regulation of genes in the tissue while down regulation of genes in diabetic liver of mice. Both in-vivo and in-vitro activity of titanium oxide and cobalt oxide nanoparticles showed that these nanoparticles are active anti-diabetic sources of drug delivery.
MIL-101(fe) derived cofe nanomaterials for electrocatalytic oxygen reduction reaction
(UMT, Lhr, 2023) WARDA ASHRAF
The combustion of fossil fuels has long been recognized as a major contributor to the increase in greenhouse gas emissions, particularly carbon dioxide (CO2), leading to the capture of heat returning from the Earth's surface and subsequent global warming. As a response to the urgent need for clean and sustainable energy, fuel cells and metal-air batteries have emerged as proven technologies. These systems rely on electrochemical reactions, with the oxygen reduction reaction (ORR) playing a pivotal role in their overall performance. Understanding the factors influencing the activity and selectivity of ORR catalysts is crucial for the development of efficient and selective catalysts, contributing to the advancement of clean energy applications. In this context, the exploration of various carbon supports, Fe precursors, and the role of nitrogen content has become an integral aspect of catalyst design. The ongoing quest for enhanced catalyst performance has led to innovative approaches, and one such approach involves the synthesis and modification of metal-organic frameworks (MOFs). In this particular study, the MOF MIL-101 (Fe) serves as the precursor for the synthesis of an efficient ORR catalyst. The MOF is subjected to a controlled sonication process with melamine, cobalt nitrate hexahydrate (Co(NO3)2.6H2O), and iron nitrate nonahydrate (Fe(NO3)3.9H2O). The resulting composite undergoes calcination under an argon atmosphere, leading to the creation of a highly effective catalyst for ORR. By adjusting the concentration of Fe(NO3)3.9H2O while keeping the concentrations of MIL-101, Co(NO3)2.6H2O, and melamine constant, various materials with distinct ratios are synthesized. Characterization of the resulting materials conducted through powder X-ray diffraction studies, providing insights into their structural composition and crystallographic features. The catalytic activity of these materials further assessed using a three-electrode system with a rotating disc electrode (RDE) serving as the working electrode. Among the synthesized materials, denoted as Co/Fe@1, Co/Fe@2, Co/Fe@3, and Co/Fe@4, Co/Fe@3 stands out as a particularly effective catalyst for selective O2 reduction. Co/Fe@3 exhibits superior ORR activity when tested in a 0.1 M KOH solution, showcasing comparable performance to the benchmark catalyst (20 wt% Pt/C). Key electrochemical parameters, such as onset potential of 0.99 V, a Tafel slope of 57 mV dec-1, current density of 5.22 mAcm-2, and a half-wave potential of 0.87 V, highlight the efficacy of the synthesized material. Notably, this material opens a pathway for the fabrication of effective ORR catalysts based on iron, a metal traditionally deemed less active in ORR processes. In summary, the synthesis and modification of MOFs for the development of efficient ORR catalysts represent a promising avenue in the pursuit of sustainable energy solutions. The meticulous exploration of various parameters in the synthesis process, coupled with comprehensive characterization and electrochemical assessments, contribute to the ongoing advancements in the field of catalyst design for clean energy applications.
Synthesis of Cellulose-Based Molecularly Imprinted Polymers for Creatinine Sensing
(UMT, Lhr, 2023) SADIA ASHRAF
Ensuring precise and dependable analysis of creatinine is crucial for promptly identifying and efficiently monitoring kidney disease in patients. To address this pressing demand, the present study focuses on developing a molecularly imprinted polymer (MIP) tailored for the detection of creatinine, designated as MIPCre. The methodology employed revolves around a cost-effective and highly selective technique utilizing metal-free Organic Photoredox-Catalyzed Atom Transfer Radical Polymerization (O-ATRP). This novel process employs a hydroxypropyl cellulose (HPC)-based macroinitiator in conjunction with methacrylic acid (MAA) as the functional monomer. The creation of MIPCre is achieved through O-ATRP, a procedure catalyzed by 4CzIPN under visible light irradiation. The significance of this approach lies in its ability to offer an efficient, easily preparable, and economically viable solution for generating molecularly imprinted polymers tailored for creatinine detection. MIPs possess inherent advantages such as reusability and high selectivity for the target molecule, attributes that are particularly desirable in clinical settings where accuracy and reliability are paramount. The synthesis procedure entails the production of a range of poly(methacrylic acid) grafted HPC (PMAA-g-HPC), which undergoes thorough characterization employing diverse analytical methods such as scanning electron microscopy (the SEM), Fourier-transform infrared (the FTIR) spectroscopy, and thermogravimetric analysis (the TGA). Significantly, the utilization of this pioneering surface-MIP approach leads to notable progressions, including achieving an exceptionally low limit-of-detection (LoD) of 6.2 µg/mL, accompanied by a broad detection range spanning from 0.1 to 14 µg/mL. These findings underscore the efficacy and versatility of the proposed methodology in sensitively detecting creatinine within a clinically relevant concentration range. Moreover, the practical applicability of the newly devised MIP sensor is assessed through extensive creatinine measurements, demonstrating its potential efficacy as a rapid, accurate, and point-of-care diagnostic instrument for monitoring kidney disease in patients Expanding beyond the technical aspects, the implications of this research extend to broader implications within the realm of healthcare and diagnostics. The development of a reliable, cost-effective, and selective creatinine sensor holds profound implications for enhancing patient care, particularly in contexts where access to sophisticated laboratory infrastructure may be limited. By enabling the early detection and continual monitoring of kidney function, the MIP sensor possesses the potential to facilitate prompt intervention and customized treatment approaches, ultimately enhancing patient outcomes and alleviating the burden of kidney disease on healthcare system. Moreover, the versatility of the MIP sensor platform extends beyond creatinine detection, with potential applications in diverse fields such as environmental monitoring, food safety, and pharmaceutical analysis. The adaptability of the synthesis methodology opens avenues for future research and innovation, including the exploration of novel MIP formulations targeting different analytes and the integration of advanced sensor technologies for enhanced performance and usability. In conclusion, this study signifies a notable advancement in the field of molecularly imprinted polymer-based sensors for detecting creatinine, presenting a hopeful approach to meet the urgent requirement for precise and readily available diagnostic instruments in managing kidney diseases. Through interdisciplinary collaboration and continued technological advancement, the MIP sensor holds the potential to revolutionize clinical diagnostics and improve patient care on a global scale.
Utilization of tobacco plant parts for synthesis of biofuels
(UMT, Lhr, 2023) MAMOONA RIAZ
Green fuels are emerging topic of research in current era due to environmental concerns (SDG7). The study was focused on the utilization of tobacco plant parts for synthesis of biofuels. Biofuels were synthesized through fermentation and catalytic cracking process. Significance of this research lies in the fact that the cost-effective catalyst and widely available feedstock was used. The feedstock was tobacco leaves, stalk and seed oil. Bioethanol was synthesized from pretreated tobacco leaves and stalk via fermentation using baker’s yeast under specific conditions. The yield of bioethanol from alkaline (CaO) pretreated tobacco leaves was 62.2% while the yield of bioethanol from hydrothermal pretreated tobacco stalk was 59.7%. The yield of bioethanol from acid catalyzed pretreatment method was very low so it was not carried out further. Biofuel was synthesized from catalytic cracking of 100ml tobacco seed oil using 1g V2O5 catalyst and 0.5 Al2O3 as a support material at 320°C for 45 minutes. Fuel properties (flash point, viscosity, density, and cloud point) were analyzed. Flash point and cloud point of bioethanol produced from alkaline pretreated tobacco leaves was 17.2°C and 19.3°C. GC-MS analysis of bioethanol predicts 11 major compounds along with ethanol in major concentration. And GC-MS analysis of bio-oil predicts 25 major compounds in it. Results suggested that alkaline pretreated tobacco leaves give high yield of bioethanol compare to hydrothermal pretreated tobacco stalk. And V2O5 catalyst has great capacity for the conversion of oil into biofuel. The yield of pyrolyzed oil was 1.1%. Hence, this research supports the recycling of biomass for the production of biofuels.
Fabrication of SNO2@znoCarbon Foam Nanocomposite for Efficient Degradation and Antibacterial Activity
(UMT, Lhr, 2023) RAHEELA RAMZAN
In this research, SnO2@ZnO/CF nanocomposite fabricated by one pot facile synthesis followed the coprecipitation route. The nanocomposite was characterized by FTIR, XRD, TGA, SEM and EDX revealed functional group, crystalline structure, thermal stability, morphology and, conformation of elements respectively. As prepared nanocomposite has a high efficiency to degrade the methylene blue on sunlight light irradiation as compared to the individual SnO2 and ZnO/CF nanocomposite. SnO2@ZnO/CF nanocomposite suppressed the charge recombination and enhanced the charge separation which increases the photocatalytic degradation activity upto 100 %. The catalyst amount, light exposure, concentration of MB was optimized. The nanocomposite can be recovered after several cycles and demonstrated degradation rate around 92 %. Antibacterial activity was evaluated against Gram-negative bacteria (E. coli) and Gram-positive (Bacillus subtilis). The high antibacterial activity of the SnO2@ZnO/CF nanocomposite is attributed to the generation of the reactive oxygen species (ROS) and the release of the metal’s ions. These reactive species destroyed the cell wall of the bacteria and kill them. Thus, it has been proven that the SnO2@ZnO/CF nanocomposite displayed high photocatalytic activity for the degradation of organic dyes, with high antibacterial activity.
Fabrication of novel vildagliptin-loaded zinc oxide nanoparticles for anti-diabetic activity
(UMT, Lhr, 2023) ABDUL SAMAD
The aim of the current study was to synthesize vildagliptin loaded ZnO nanoparticles for enhanced efficacy in terms of increased retention time, minimize side effects and increased hypoglycemic effects. Diabetes mellitus is the fastly prevailing disease throughout the world. Vildagliptin is the standard drug which is used for the treatment of diabetes. But the drug has certain limitations associated with it which includes short half-life and high dosage frequency. Now a days, Nanotechnology has revolutionized in every field of life. In medicine, nanoparticles are used as safe drug carriers, as nano-medicines with increased bioavailability, in tissue engineering and in diagnosis of diseases. Various nanoparticles like ZnO nanoparticles itself have medicinal applications. In this work, ZnO nanoparticles were synthesized by precipitation method and then drug vildagliptin was loaded on them by batch adsorption method. Ultraviolet Visible spectroscopy, Fourier transform Infra-red spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), High performance liquid chromatography (HPLC) and Energy Dispersive Xray (EDX) analysis were performed for the characterization of synthesized Vildagliptin loaded ZnO nanoparticles. The morphology of the synthesized drug loaded nano-material was analyzed by SEM which shows the formation of product with flaky texture. The crystallinity of drug loaded nano-materials was analyzed by XRD which gave the average crystalline size of 21.94 nm. EDX analysis detected the presence of Carbon, Oxygen, Zinc and Nitrogen in the product. The drug loading efficiency was determined by using HPLC method. The maximum adsorption efficiency of 58% was obtained. Further, In vitro anti-diabetic activity was assayed by determining the α-amylase and DPP IV inhibition activity of the product formed. The formulation gave maximum inhibition of 82% and 94% of α-amylase and DPP IV respectively at concentration of 1000 µg/ml. The inhibition of α-amylase can be attributed to synergistic effect of ZnO nanoparticles and vildagliptin.
Synthesis and characterization of silver(i) metal organic framework/polyvinylpyrrolidone composite thin film with antibacterial performanc
(UMT, Lhr, 2023) HUMAIRA SHAHEEN
Metal-organic frameworks (MOFs) have significant antibacterial characteristics that make them suitable for use as antibacterial agents. In this work, polyvinylpyrrolidone (PVP) polymer membrane casting solution and the hydrophobic Ag-MOF was combined by phase inversion technique to produce Ag-MOF@PVP thin film composite. Using a variety of analytical methods, including X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR), the chemical and physical properties of the generated materials were investigated. FTIR study verifies the presence of the Ag-based MOFs' functional group, while X-ray analysis demonstrates the structure's crystallinity. The antibacterial efficacy of Ag-MOF and the Ag-MOF@PVP composite against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was assessed using the zone of inhibition and minimum inhibitory concentration (MIC) assays. The effective synthesis of Ag-MOF and Ag-MOF@PVP thin film composite is eventually confirmed by the results of all analyses.
Preparation of Cu-SiO2g-C3N4 Composite for the Removal of Pollutants from the Wastewater
(UMT, Lhr, 2023) HAFIZA HINA JAVED
In this work, copper-doped silica (Cu-SiO2)@g-C3N4 has been prepared to get a composite material. The composite material served as novel catalyst for the photocatalytic degradation (upto 99%) of a model dye methylene blue. In the presence of sunlight. In addition, the catalyst successfully inhibited some famous types of pathogens (E.Coli.and B. Subtilus) present in the polluted water. The composite material was characterized using various techniques for the surface morphology, stability and particle size. These analyses included spectroscopy, X-ray diffraction, scanning electron microscopy, and elemental analysis. The prepared composite material has the ability to reduce charge recombination and increase charge separation during the excitation in the presence of sunlight. The production of reactive oxygen species (ROS) at the surface of metal ions were thought to be responsible for the powerful antibacterial capabilities of the Cu-SiO2/g-C3N4 combination. These reactive species efficiently pierced the cell walls of the bacteria, which ultimately led to their extinction. Our results emphasize the strong antibacterial capabilities and extraordinary photocatalytic activity of the Cu-SiO2/g-C3N4 composite in degrading organic dyes, indicating its potential for a wide range of environmental and biological applications.
Synthesis and Characterization of Chromium doped SnO2 at Reduced Graphene Oxide Nanocomposite and its Electrochemical Measurements
(UMT, Lhr, 2023) MADARAQA AFTAB
In this study, chromium doped tin oxide loaded on reduced graphene oxide nanocomposites were synthesized via a co-precipitation approach. Pure and Cr (2, 4, 6, 8 and 10%) doped SnO2 nanoparticles were also prepared through similar method. Optical, structural and morphological characteristics of samples were carried out by FE-SEM, XRD, UV–Visible characterizations. The morphology observed through SEM, 8% Cr-SnO2 at RGO is in form of nanorods. XRD studies confirmed the diffracted peaks were rutile structure of SnO2 phase. Study was conducted in various electrolytes but best result was found in KOH. The electrochemical behavior of the sample was determined using Cyclic Voltammetry (CV) by scanning the potential at a rate of 50 mV s‾¹ and for a maximum current of 750 mA carried out on all samples. It was observed that as the weight percentage of Cr in Cr doped SnO2 increases, the electrochemical performance increases as compared to pure SnO2. The sample showed both oxidation and reduction peaks. A larger peak current of 8mA and oxidation potential of 0.69V was observed for 8 weight percent Cr doped SnO2. It also exhibited the highest areal capacitance of 401 F/g at a scan speed of 50 mV s−1, which is higher than that of the pure SnO2 (246.5 F/g). More electrolyte was mobilized at 8% Cr-SnO2 surface rather than 10% Cr-SnO2 surface. 8% Cr doped SnO at RGO showed peak current at 16 mA and oxidation potential was 0.7V. It also showed enhanced conductivity between graphene sheets, thus improving the charge transfer and specific capacitance (830 F/g). The electrochemical behavior of the sample was further determined using Electron Impedance Spectroscopy by applying direct voltage of 0.7V, 8% Cr doped SnO2 at RGO showed a closed curve in high frequency area indicating stability and more impedance compared to other samples.
Removal of fluoride by using biochar; a step toward sustainable environmental remediation
(UMT, Lhr, 2023) GHAZALA YASEEN
The thermochemical conversion of agricultural waste to biochar opens up new possibilities for environmentally sustainable waste management. Biochar is widely applicable in the field of waste-water treatment because of utilizing a variety of physical and chemical activation methods to change its structural and physicochemical properties to fit the ultimate use. The main purpose to conduct this study was to remove the fluoride ion by using banana and grapefruit peels biochar. Biochar was chemically treated with ZnCl2 and sodium dodecyl sulfate. Ion selectiveelectrode was used for quantitative study the batch wise adsorption of fluoride optimizing by different parameters such as; time contact, adsorbent dosage, pH, anion concentration as well as temperature. Different isothermal, kinetic and thermodymics models were studied in order to investigate the adsorption behavior of biochar. Biochar was characterized by Scanning electron microscope (SEM) for surface morphology, FT-IR for functional groups and Thermogravimetric Analysis (TGA) for the thermal stability. Carbon, Hydrogen, nitrogen and Sulfur was used to scrutinize the elemental conformation of biochar obtained from agricultural waste. The results showed that biochar prepared from banana and grapefruit peels are considered among eco-friendly and inexpensive adsorbents to eliminate fluoride ion from the aqueous medium.
Synthesis of CdS@ZnOCF Nanocomposite for Enhanced Photocatalytic Degradation and Antibacterial Activity
(UMT, Lhr, 2023) SIDRA TARIQ
Environmental pollution caused by the improper disposal of waste materials, particularly organic dyes from various industries into water bodies is considerable. It is important to do comprehensive studies on photocatalytic materials in order to effectively remove dangerous contaminants from water. In this respect porous carbon based materials have drawn great attention due to their novel properties. In this work, CdS@ZnO/CF nanocomposite has been prepared by the hydrothermal method. The nanocomposite was characterized by FTIR, XRD, TGA, SEM and EDX. The prepared nanocomposite has a high efficiency to degrade the methylene blue under sunlight light irradiation as compared to the individual CdS and ZnO/CF nanoparticles. CdS@ZnO/CF nanocomposite decrease the charge recombination and increase the charge separation which enhance the photocatalytic degradation activity (up to 98%). The catalyst amount, light exposure, concentration of MB were optimized. After comprehensive experiments 0.04g catalyst , 100mW/cm2 for 80mins light exposure, 30ppm concentration of MB were selected as optimum values for further analysis. The nanocomposite was recovered after several cycles and demonstrated degradation rate around 90 %. In addition, the CdS@ZnO/CF nanocomposite successfully inhibited famous type of pathogens (E.coli, Bacillus subtilis). These pathogens showed higher activity of 30mm and 15mm at 300ppm solution of catalyst. The generation of the reactive oxygen species (ROS) at the surface of metal ions were thought to be important for the powerful antibacterial activity of the CdS@ZnO/CF nanocomposite. These reactive species penetrated into the cell wall of the bacteria which leads to their destruction. Thus, it has been proven from results that the CdS@ZnO/CF nanocomposite showed remarkable photocatalytic activity for the degradation of organic dyes, with strong antibacterial activity.
Micro determination of minerals and anti-oxidant activity in different mushrooms of swat valley by spectroscopic techniques
(UMT, Lhr, 2023) Sana Ashraf
Mushrooms are known to mankind since early human civilization and gradually gained importance due to their medicinal and nutritional properties. These are also origin of mineral nutrients, proteins and carbohydrates Mushrooms are important fungi used in complementary medicine. Helvella spp. are found most abundantly in Himalayan moist temperate forests of Pakistan. Native people are using these mushrooms since centuries. For the first time, mineral analysis and anti-oxidant activities of Helvella spp. have been reported from Pakistan. This study gives attention to expose their mineral profiles by Flame photometery, Atomic absorption spectroscopy and Spectrophotometry. Biological activities focusing on antioxidant activities based upon lyophilized sequential extracts and traditional preparations attain from the fruit bodies of these mushrooms. The present study revealed that Helvella acetabulum are most enrich in sodium (53mg/100mg) and Helvella paraphysiorquata showed highest trace element iron (0.51mg/100mg) concentration. The most active oxygen inhibitor and enzyme inhibitory extracts were shown by H. paraphysitorquata. Information obtained from this data reveals that H. paraphysitorquata used as raw materials in food, pharmaceutical industries, nutraceutical and biotherapeutic. The results suggested that mushrooms can be ingested as a functional food and employed as a therapeutic element due to its bioactive substances and its well-balanced nutritional profile. Hopefully the selected mushroom species will further be analyzed and used it in daily diet to reduce the deficiency of micronutrients in people.
Designing Highly Efficient Ternary Nanocomposite ComnsS-g-C3N4 for Bacterial Disinfection and Visible-light Photocatalysis of Organic Dye
(UMT, Lhr, 2023) YASMEEN KHAN
In this project, an eco-friendly, simple and low-cost co-precipitation method was adopted to synthesize pure MnS and a series of Co/MnS NPs with various contents of cobalt (2 %, 4 %, 6 %, 8 % and 10 %). The calcination of thiourea was done at 550 oC to prepare S-g-C3N4 nanosheets. The best doped NPs were then mixed with S-g-C3N4 to prepare a series (10 %, 30 %, 50 %, 70 % and 90 %) of nanocomposites. The band gap (Eg) values of materials were determined by using tauc plot. The photodegradation of MB dye was performed using a UV-Vis. spectrophotometer. According to the results, the doping of 6 % cobalt into the MnS lattice improved the photocatalytic oxidation/reduction. However, the overall best photodegradation was shown by 6Co/MnS@10SCN NCs. The photocatalytic efficiency was enhanced by using 6Co/MnS@10SCN NCs due to the enhancement of charge separation and suppression of charge recombination. Even after three cycles, it was possible to recover the synthesized nanocatalysts with significant % degradation. The structural morphologies of pure MnS, 6 % Co/MnS, S-g-C3N4 and 6Co/MnS@10SCN NCs were examined by using XRD and FTIR. The kinetic study of prepared nanomaterials was performed to determine their rate constant. Bacillus subtilis and Escherichia coli bacteria were selected to test the antibacterial performance of best photocatalysts. It can be inferred from results that the composite synthesis and doping boosted the antibacterial activity of MnS.
Storage and permeation of gaseous and ionic species through silicon carbide
(UMT, Lhr, 2023) FAREEHA GHAFFAR
Silicon carbide is made of carbon and silicon where the atoms of each element forming tetrahedral bonds with the other four atoms in the compound. In research, point of view silicon carbide has fascinating electronic properties. Silicon carbide nanotube is suitable material for various applications because of their good mechanical strength high thermal resistance and high chemical stability and as semiconductors. In the present works, the silicon carbide nanotubes is examined has ability for storage and permeation of gaseous and ionic species. For this, the thermodynamic stability and electronic properties of SiC complexes are determined by using different computational methods. ꞶB97XD and B3LYP functional with 6 31+G(d,p) basic set of exohedral and endohedral gaseous species doped silicon carbide complexes. The kinetic barriers for different types (small and large size) of species (gaseous and ionic) through silicon carbide are calculate by scanning (PES) potential energy surface. By measuring the (GH-L) that is called energy gap is analyzed which is justified from (DOS) density of state of spectra. All the exohedral species doped in silicon carbide are exothermic while the endohedral species doped with silicon carbide are endothermic in nature, and also conclude that all the endohedral complexes are less prominent while the exohedral complexes are more prominent then the endohedral complexes that effect on the electronic properties. By studying the GH-L that tells us the endohedral complexes have lower gap as compared with exohedral doped SiC nanotubes.
Fabrication of Si12C12 Nanocage with First Row Transition Metals to act as Single Atom Catalyst for HER reaction
(UMT, Lhr, 2023) Saira Rafiq
In this research work, doped nanocage of silicon carbide is investigated. The adsorbtion of hydrogen at doped TM@SiC reveals that stability of nanocage is significantly improves. In this work, we investigated the many properties such as geometry, electronic properties, NBO, NCI plots of various doped nanocages of Silicon Carbide (Zn@ Si12C12, Fe@ Si12C12, Co@ Si12C12, Cu@ Si12C12 and Ni@ Si12C12). All calculations are calculated at the same level of B3LYP/631-G(d). All the doped structures reveal that nanocage complexes have highest interaction energies from 0.4 to -0.69 eV and Cu@Si12C12 plays an excellent role in HER due to values 0.17 eV which is near to zero. Cu@Si12C12 shows the excellent activity in stability and HER due to lower values -3.30 eV. According to NBO calculations, it is observed that charge transferred from doped transition metals towards nanocage which leads to stability of nanocage. After H adsorbtion, NBO charge transfer to hydrogen which shows the adsorbtion properties of H. In case of HOMO-LUMO energy gap, it is observed that nanocage of doped transition metals have small energy gap from 0.0 eV to 2.7 eV but after adsorbtion of hydrogen, this energy difference between the gap leads to change from 0.1 eV to 3.7 eV which also verify the stability of nanocage. DOS spectra’s showed the formation of new bonds due to difference in electron density that shifts. NCI plots also explained the different types of bonding in doped nanocage.

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